1. Field of the Invention
This invention relates to a bezel which is mounted on a front face of a cathode ray tube (CRT) of a television set or the like.
2. Description of the Prior Art
A display unit such as a television set normally employs a CRT. and a bezel is mounted on a front face of such CRT. An exemplary one of conventional display units which employ a CRT is shown in FIG. 6. Referring to FIG. 6, a bezel 2 is mounted on a front face of a CRT 1 such that a tube face 1a of the CRT 1 is exposed forwardly through a substantially rectangular opening 2a of the bezel 2. The bezel 2 is secured to the CRT 1, for example, by means of a plurality of fastening screws N which extend through coupling tabs 1b of the CRT 1 and are screwed into threaded holes 2b of the bezel 1 shown in FIG. 7.
The bezel 2 has a rib 2d formed thereon at a portion thereof at which it contacts with the CRT 1, that is, a peripheral portion of the bezel 2 around the opening 2a. Referring to FIGS. 7 and 8 the rib 2d extends along a frame portion 2c formed along the entire inner periphery of the bezel 2 around the opening 2a and has an offset or step of, for example, 0.3 to 0.5 mm from a face 2c of the frame portion 2c opposing to the tube face 1a of the CRT 1. The bezel 2 is thus held in contact at the rib 2d thereof with the tube face 1a of the CRT 1 as seen in FIG. 8.
However, since it is not preferable for the sake of a good appearance of the display unit that a great gap is provided between opposing faces of the CRT 1 and the bezel 2, it is difficult to have a great contact area between the rib 2d of the bezel 2 and the tube face 1a of the CRT 1.
Consequently, the width of the contacting face of the bezel 2, that is, the width of the rib 2d, is limited. Besides, since the rib 2d is provided on the entire inner periphery of the bezel 2, a considerable variation occurs among bezels upon molding, and quality control in the accuracy of the rib height is very difficult.
The small area of the contacting face of the bezel 2 gives rise to another problem. In particular, while such bezel is normally molded from a plastic material such as an ABS resin, fine powder often drops, after the bezel 2 is assembled, from the surface of the rib 2d of the bezel 2 due to rubbing between the tube face 1a of the CRT 1 and the rib 2d which occurs during transportation of the CRT 1 or the like, and such fine powder often appears on the tube face 1a of the CRT 1 and gives a bad influence on the appearance of the display unit.